Sorry if I've put the thread in the wrong place. Anyway. My quiestion is as follows.

What simcard is the best solution for travellers in Europe who need to have Internet connection throughout the day on their phones. I have been searching by myself for a while and came to the conclusion that most companies make accent on offering solutions for those who do phone calls. What I need more is the Internet on my mobile phone, fast, good, and stable. I am going to use wifi router and supposedly need around 1gb or more.

Always remember that roaming rates in the EU will be changing twice in the next couple of months, because of the new EU roaming rules.
These "roaming SIM cards" featured on the WIKI are good for the moment. But roaming prices will probably fall by 30th of April 2016 and most EU roaming surcharges will (hopefully) be over by mid 2017.

Right now various operators react very differently to the new EU guidelines: E.g. in Germany Telekom will go down to 5ct/MB for roaming on most of its plans while it's competitor Telefónica (Eplus, O2) has announced, that they will keep on charging 23ct/MB for many plans on roaming.

When the situation about the new rates starting in May 2016 becomes clearer, the data WIKI will be revised on Europe. As a rule of thumbs: For low data volumes (like up to 200-300 MB) and calls and SMS, it will be easier and cheaper to stay on roaming of an EU-issued SIM. For higher data consumption, you'd still better buy a local SIM or (if travelling several countries) one of the "roaming SIMs" featured on the WIKI.

It seems that most prepaid platforms are not able to distinguish between having a domestic bundle active or not in order to apply different roaming price. Therefore most operators seem to set prices for prepaid roaming from May on somewhere at the EU provided surcharge amounts without adding any domestic base price.

I do not think that O2 Germany will be able to charge 0,23 € / MB in EU-roaming as almost all their prepaid tariffs include domestic allowances which means that O2 is not allowed to charge more than a surcharge which in Germany is not allowed to reach 0,06€/MB.

The regulated prepaid roaming price differences between the different EU operators seem to be minimum. The Spanish operators Orange and Movistar managed to surpass the allowed amounts applying the rounding up, strictly forbidden by the EU regulation. Vodafone UK seems to have one of the better offers on its PAYG/prepaid with free incoming calls:
EU(except UK) to EU call: 4p/min
EU(except UK) to EU SMS: 1p
Incoming calls in the whole EU: free
Data in the EU (except UK): 4p/MB

The interesting part are the prepaid tariffs, e.g. the Smart one:
200 minutes or SMS and 750 MB allowance inside Germany (9,99 EUR/28 days) usable without surcharge also in the whole EU/EEA. At least that is how most people understand the mentioned pricelist. It is not clear from there whether the incoming calls are free or charged at 1,36 ct/min.

Should this data show as correct, I think that many special roaming solutions like Toggle Mobile, Lycamobile, Travelsim, etc. will completely lose their importance inside the EU.

Unfortunately, it hasn't proven as correct. Vodafone had some "communication issues". Summing up all tariffs/plans for EU roaming are between roughly 6ct/MB and 24ct/MB. All providers try to push the rate up to the legal limit (some may even go beyond).

What is missing is a roam like home plan possibly for a surcharge. A package with the usual allowances that you use at home (may be for a reasonable surcharge) to be used abroad. That's what customers expect. Now, the heavily advertised reduction of roaming fees will not prevent shock bills (500 MB can still be sold for 115€), nor does it offer any new choices for regular users. Only some light users will benefit, if they happen to be on the right plan.

In a few days I will start a new thread here. I'm still hoping that some EU providers will eventually coming up with new, improved packages. Some EU packs simply don't make sense anymore. They are now more expensive than the default per-MB rate. So from end of April let us collect offers of EU roaming packages from EU operators that users can take abroad to other EU countries. I cannot believe that there will be no better ones than before. The best offers will be published on the prepaid data WIKI. Having said this, you still can't avoid buying a local SIM in your destination country, if you want to use >300 MB at a reasonable rate.

In a few days I will start a new thread here. I'm still hoping that some EU providers will eventually coming up with new, improved packages. Some EU packs simply don't make sense anymore. They are now more expensive than the default per-MB rate. So from end of April let us collect offers of EU roaming packages from EU operators that users can take abroad to other EU countries. I cannot believe that there will be no better ones than before. The best offers will be published on the prepaid data WIKI. Having said this, you still can't avoid buying a local SIM in your destination country, if you want to use >300 MB at a reasonable rate.

It seems that fear of the demise of the need for this forum for Europe are premature.
While I currently do not foresee a visit to Europe in the near future it looks like it will
be quite interesting in the cellular data market for the foreseeable future.